Module blocking 

Available on crate feature block-detect only.

Heuristic blocking-call detection inside async tasks.

Available with the block-detect feature.

When an async task contains a synchronous I/O call (e.g. std::fs::read instead of tokio::fs::read), the runtime cannot preempt it, and other tasks on the same worker stall. This module provides a heuristic detector: wrap an async block, and if it takes more than max_no_yield real time without yielding, flag it.

Heuristic, not deterministic

This cannot perfectly distinguish “blocking call” from “long synchronous work between awaits”. A long pure-CPU section also looks like blocking from this detector’s perspective. Treat the verdict as a signal to investigate, not a proof.

Functions

detect_blocking

Wrap a future and emit a CheckResult flagging suspected blocking calls inside it.